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4 Aug 2026
A chimpanzee lies in a sleeping nest in a tree canopy in Tanzania's Gombe Stream National Park. dpa/picture alliance/Alamy Stock Photo
Why Humans Are the Sleepless Apes of the Animal Kingdom
Warm-up → Read & Listen → Check Understanding → Language → Use It
WARM UP
Think Ahead: Which detail do you think appears in this story?
a) Humans sleep more than monkeys.
b) Early humans slept on the ground.
c) Chimpanzees do not sleep at night.
Ask:
(1) How many hours do you sleep every night?
(2) Do you like sleeping in a big bed?
VOCABULARY
Human /hjumən/
noun
Sleep /slip/
verb
Animal /ænɪməl/
noun
Night /naɪt/
noun
Deep /dip/
adjective
Protect /prətekt/
verb
Definition: A person, not an animal or plant.
Example: A human needs food and water every day.
Definition: To rest your body and mind with your eyes closed.
Example: I sleep for eight hours every night.
Definition: A living creature that is not a human or plant.
Example: A dog is a friendly animal.
Definition: The time when it is dark and people go to bed.
Example: Stars shine bright in the night.
Definition: Going far down or strong.
Example: He fell into a deep sleep after playing sports.
Definition: To keep someone or something safe from danger.
Example: Parents protect their children from harm.
Did you know that humans sleep less than most animals? A chimpanzee sleeps for twelve hours every night. A monkey can sleep for ten hours. However, a human only sleeps for about seven hours.
Scientists say that humans are the sleepless apes. Long ago, early humans slept on the hard ground. They did not sleep high up in safe trees like other primates. Because of dangerous animals, they had to stay alert and protect their family group.
Fire also changed how humans lived. When early humans made fire, they could sit together at night. They talked, cooked food, and learnt new things in the dark.
Even though humans sleep less, our sleep is very special. We have more deep sleep than other animals. This deep sleep helps our brain stay healthy and strong. So, you do not need to sleep all day like a lazy cat to feel great!Sleep_
Listen
Author David Samson has climbed trees to study chimpanzee nests in his quest to understand how human sleep evolved. Bill McGrew
DISCUSSION QUESTIONS
1. How many hours of sleep do you get every night?
2. What time do you go to bed during the school week?
3. Why do you think early humans needed fire at night?
4. Do you like sleeping in total darkness or with a small light?
5. What happens when you do not get enough sleep?
FILL IN THE GAPS
FILL THE GAPS
Section 1: Fill in the Gaps
Word Bank: animals, deep, night, protect
Did you know that humans sleep less than most _______(1)? A chimpanzee sleeps for twelve hours every night. A monkey can sleep for ten hours. However, a human only sleeps for about seven hours.
Scientists say that humans are the sleepless apes. Long ago, early humans slept on the hard ground. They did not sleep high up in safe trees like other primates. Because of dangerous animals, they had to stay alert and _______(2) their family group.
Fire also changed how humans lived. When early humans made fire, they could sit together at _______(3). They talked, cooked food, and learnt new things in the dark.
Even though humans sleep less, our sleep is very special. We have more _______(4) sleep than other animals. This deep sleep helps our brain stay healthy and strong. So, you do not need to sleep all day like a lazy cat to feel great!
Section 2: Main Idea
What is the main idea of the article?
a) Monkeys sleep on top of tall trees.
b) Humans sleep fewer hours than animals, but our sleep is deep and special.
c) Fire helps animals sleep better at night.
UNDERSTANDING
Section 3: True or False
1. Chimpanzees sleep for twelve hours every night. T/F
2. Early humans slept high up in safe trees. T/F
3. Deep sleep helps the human brain stay healthy. T/F
Section 4: Put Events in Order
Put the following events in order from 1 to 3: -
A) Early humans made fire and talked together at night.
B) Early humans started sleeping on the ground instead of in trees.
C) Deep sleep helps modern humans keep their brains strong.
LANGUAGE
Section 5: Vocab Match
1. Human
2. Sleep
3. Animal
4. Night
5. Protect
a) A person, not an animal
b) The dark time when people rest
c) To keep someone safe from danger
d) A living creature like a dog or lion
e) To rest your eyes and mind at night
USE IT
Section 6: Discussion Builder
1. I usually go to _______ at nine o'clock.
a) sleep
b) tree
c) fire
2. Parents always _______ their children from danger.
a) sleep
b) protect
c) talk
Section 7: Sentence Unscramble
Unscramble the words to make correct sentences:
1. A) sleeps / B) chimpanzee / C) twelve / D) hours / E) A
2. A) Humans / B) sleep / C) less / D) animals / E) than
ANSWER KEY
Warm Up Answer: b
Section 1: Fill in the Gaps
animals
protect
night
deep
Section 2: Main Idea
Answer: b
Section 3: True or False
True
False
True
Section 4: Put Events in Order
Early humans started sleeping on the ground instead of in trees.
Early humans made fire and talked together at night.
Deep sleep helps modern humans keep their brains strong.
Section 5: Vocab Match
1-a, 2-e, 3-d, 4-b, 5-c
Section 6: Discussion Builder
a
b
Section 7: Sentence Unscramble
E - B - A - C - D (A chimpanzee sleeps twelve hours)
A - B - C - E - D (Humans sleep less than animals)
Section 8: Discussion Questions
(Student responses will vary)
Thank you for your feedback!